package cn.atfaith.controller;

import org.springframework.stereotype.Component;

import javax.websocket.*;
import javax.websocket.server.PathParam;
import javax.websocket.server.ServerEndpoint;
import java.util.Objects;
import java.util.concurrent.CopyOnWriteArraySet;

/**
 * 只能群发
 *
 * @author ZHAOAC
 * @creat 2021-03-12 14:59
 */
@ServerEndpoint(value = "/websocket/{nickname}")
@Component
public class WebSocketServer {
    /**
     * 用来存放每个客户端对应的 WebSocketServer 对象
     */
    private static CopyOnWriteArraySet<WebSocketServer> webSocketSet = new CopyOnWriteArraySet<>();

    /**
     * 与某个客户端的连接会话，需要通过它来给客户端发送数据
     */
    private Session session;
    private String nickname;

    /**
      * 连接建立成功调用的方法
      */
    @OnOpen
    public void onOpen(@PathParam("nickname")String nickname, Session session) {
        this.session = session;
        this.nickname = nickname;

        //加入set中
        webSocketSet.add(this);

        System.out.println("有新连接加入:"+nickname+",当前在线人数为" + webSocketSet.size());
        this.session.getAsyncRemote().sendText("恭喜"+nickname+"成功连接上WebSocket(其频道号："+session.getId()+")-->当前在线人数为："+webSocketSet.size());
    }

    /**
     * 连接关闭调用的方法
     */
    @OnClose
    public void onClose() {
        //从set中删除
        webSocketSet.remove(this);
        System.out.println("有一连接关闭！当前在线人数为" + webSocketSet.size());
    }

    /**
     * 收到客户端消息后调用的方法
     *
     * @param message 客户端发送过来的消息
     */
    @OnMessage
    public void onMessage(String message, Session session) {
        System.out.println("来自客户端的消息-->"+nickname+": " + message);

        //群发消息
        broadcast(nickname + ":" + message);
    }

    /**
     * 发生错误时调用
     */
    @OnError
    public void onError(Session session, Throwable error) {
        System.out.println("发生错误");
        error.printStackTrace();
    }

    /**
     * 群发自定义消息
     */
    public  void broadcast(String message) {
        for (WebSocketServer item : webSocketSet) {
            //同步异步说明参考：http://blog.csdn.net/who_is_xiaoming/article/details/53287691
            //this.session.getBasicRemote().sendText(message);

            //异步发送消息.
            item.session.getAsyncRemote().sendText(message);
        }
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        WebSocketServer that = (WebSocketServer) o;
        return Objects.equals(session, that.session) && Objects.equals(nickname, that.nickname);
    }

    @Override
    public int hashCode() {
        return Objects.hash(session, nickname);
    }
}